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Discrete process

Most of this chapter is concerned with discrete systems such as those in parts b, c, d of Pig. 4-1. These are systems in which the messages going into and out of the coder and decoder can be represented as sequences of symbols from a finite alphabet. While information theory can be generalized to deal with continuous processes, this generalization is best treated as a limiting operation on discrete processes. [Pg.192]

The precipitation of calcium carbonate in the boiler involves a number of discrete processes, including nucleation, followed by the formation of microcrystals which compete to grow into larger crystals (accretion) that eventually form layers of dense, crystalline scale on the heat exchange surface. [Pg.224]

The problems relating to mass transfer may be elucidated out by two clear-cut yet different methods one using the concept of equilibrium stages, and the other built on diffusional rate processes. The selection of a method depends on the type of device in which the operation is performed. Distillation (and sometimes also liquid extraction) are carried out in equipment such as mixer settler trains, diffusion batteries, or plate towers which contain a series of discrete processing units, and problems in these spheres are usually solved by equilibrium-stage calculation. Gas absorption and other operations which are performed in packed towers and similar devices are usually dealt with utilizing the concept of a diffusional process. All mass transfer calculations, however, involve a knowledge of the equilibrium relationships between phases. [Pg.321]

Let us now illustrate the discretization process using the vibration of a triatomic molecule (ABC) as an example. The nuclear Hamiltonian with zero total angular momentum (J = 0) can be conveniently written in the Jacobi coordinates (h = 1 thereafter) ... [Pg.287]

The product of m and G, could be replaced by a new elasticity, which for convenience we could write as Gj. Equations (4.41) and (4.42) describe the relaxation of the stress in terms of a distribution of discrete processes. Some processes may be broadly separated in time to give two clearly separated relaxation processes. Other systems may show a distribution of elastic processes very closely separated in time. [Pg.114]

While site characterization can be considered and implemented as a discrete process, it is important to regard it as an element of the threat evaluation process. In particular, site characterization is an activity initiated in response to a possible accidental... [Pg.107]

Expressions for the drift velocity and diffusivity of the solution of Ito SDE (2.226) may be obtained by calculating the first and second moments of AZ for the underlying discrete process. Taking the average of AX in Eq. (2.227) immediately yields a drift velocity, as defined by Eq. (2.223), that is equal to the drift coefficient A (X) that appears in the Ito SDE ... [Pg.120]

Actually, the purpose of subtracting median values and Z-transformation in each data is only to improve visualization they do not change the results as the following discretization process is based on rank values. [Pg.64]

Equation (3.24) requires that the production volume allocated to a plant does not exceed technical capacity of the plant. Capacity consumption factors are site-specific to account for productivity differences and time dependent to allow for discrete process improvement projects. A plant s technical capacity is calculated by multiplying the number of production lines installed with the capacity per line (3.25). It can be varied between a lower and an upper bound (3.26). Restriction (3.27) states that from each plant class only one plant can be open at a site. The rationale behind this restriction is that only one plant type (size and degree of automation combination) should be put in place at a given site and capacity can be adjusted via the number of production lines. It is not implied that all production lines necessarily have to be in one building. For sites with utility capacity restrictions, constraint (3.28) ensures the available capacity is not exceeded. [Pg.100]

Despite closely reasoned counter-arguments (DeMore and Benson, 1964), the commonly held view, due to Skell, is that singlet carbenes add to olefins in a stereospecific cia-manner, whereas attack by triplet carbenes leads to non-stereospecific addition (Skell and Woodworth, 1956). The rationale of this view is that a singlet carbene should react with the olefin to form a cyclopropane in a one-step, concerted process because in this way it could occur with conservation of spin (equation 23) the addition would thus be stereospecifically cis. On the other hand, a concerted addition of a triplet carbene would violate the rule of spin conservation in consequence, a multistep reaction, in which spin inversion of an intermediate 1,3-diradical constitutes a discrete process... [Pg.194]

Dynamic sets of process-model mismatches data is generated for a wide range of the optimisation variables (z). These data are then used to train the neural network. The trained network predicts the process-model mismatches for any set of values of z at discrete-time intervals. During the solution of the dynamic optimisation problem, the model has to be integrated many times, each time using a different set of z. The estimated process-model mismatch profiles at discrete-time intervals are then added to the simple dynamic model during the optimisation process. To achieve this, the discrete process-model mismatches are converted to continuous function of time using linear interpolation technique so that they can easily be added to the model (to make the hybrid model) within the optimisation routine. One of the important features of the framework is that it allows the use of discrete process data in a continuous model to predict discrete and/or continuous mismatch profiles. [Pg.371]

The currently available data indicate that seven or eight discrete processes including Type I—III Ac-Pd reactions can take place under carbonylative conditions. In many cases, non-carbonylative cyclic carbopalladation has been observed even in the pressure of CO. A summary of all of these observed processes is presented in Scheme 13 as a guide map . [Pg.9]


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